One current Rainhill High teacher has told the Reporter working at the school, which is regarded as one of the best-performing in the borough, as “hell”, with excessive demands made on teachers.

However, a council spokesman said the formal process had not yet started as the unions had not yet come forward to cite examples of intimidation.

He added: “The school’s Chair of Governors has asked all employees and NASUWT to come forward with specific concerns and evidence and has asked the council to investigate anything they receive.

“To date no response has been forthcoming from NASUWT or employees at the school.”

Speaking about the planned strikes, Chris Keates, NASUWT General Secretary, said: “The NASUWT remains committed to seeking to resolve the issues under dispute and hopes that the employer will work with the union to fully address our members’ concerns so that further strike action can be avoided.”

Bevanie Robinson, NASUWT National Executive Member for Merseyside and Cheshire, said: “The NASUWT remains committed to seeking to resolve the issues under dispute, but will always act to support members who are being subjected to unacceptable practices and intimidation by management.

“We sincerely hope that further strike action can be avoided and would implore the employer to agree to meet with us to discuss our members concerns.”

A Rainhill High School spokesman said: “Despite any strike action, Rainhill High School will remain open for all students.

“The NASUWT have threatened 14 days of strike action between 28 March and the end of May 2017.

“This is under their national dispute with the Government.

“The school will remain open as the NASUWT only represents a minority of the teachers at Rainhill High School.

“The school is keen to resolve this and has referred this matter to ACAS, and the Trustees are happy to meet with NASUWT and ACAS to resolve these issues.”